Among humans, however, scent is less vital and more luxurious. For instance, descriptions of smell have sometimes percolated into literature. Authors such as Charles Baudelaire, Marcel Proust, and Albert Camus have produced works that tie rich scent references to emotions.

These literary works inspired study co-author Denise Chen, a sociochemist at Rice University in Texas, to wonder if there was a link between smell and emotions.

"They share close functional and anatomical connections," she said.

"The olfactory brain overlaps with the emotional brain, and is believed to have contributed to its evolution," Chen said.

Sensitive Smellers

Women have a more uniform sense of smell than men, and are also thought to be more sensitive to emotional cues, scientists have found.

So Chen and graduate student Wen Zhou presented 22 pairs of young women living in university dormitories with identical t-shirts to sleep in.

After being worn for one night, the t-shirts were later presented to the same women to smell.

Each woman was given three t-shirts and informed that one of the shirts had been worn by her roommate, and that the other two had been worn by other university students.

The subjects were asked to identify the shirt that had been worn by their roommate.

The women then took a series of recognized emotional-sensitivity tests.

Subjects who correctly selected the t-shirt worn by their roommates tended to score high on the emotional tests.

The researchers concluded that sense of smell and emotion come from the same areas of the brain.

Results published in an upcoming edition of the journal Psychological Science.